Effect of solvents on inhibition of collagen-bound proteases by chlorhexidine

Chlorhexidine (CHX) incorporation during dentine bonding with dental adhesives enhances bond durability. Choosing an appropriate solvent for CHX to enhance resin–dentine bond durability is important. This study was conducted to examine the effect of solvents on the inhibition of dentine collagen-bound proteases by chlorhexidine. The inhibitory effects of CHX (0.2% and 2%) incorporated in three different solvents (water/ethanol/acetone) on the inhibition of dentine matrix-bound proteases were investigated by assessing the change in dry mass of demineralized dentine beams and the release of solubilized collagen peptides after 30 days. Solvents without CHX were used as controls. The beams treated with 2% CHX exhibited significantly lesser loss of dry mass and hydroxyproline release when incorporated in ethanol than in water (p<0.05). No significant difference in the inhibitory effect on dentine matrix-bound proteases was found between 0.2% and 2% CHX (p>0.05). The incorporation of 2% chlorhexidine in ethanol showed greater inhibitory effect on dentine matrix-bound proteases than in water.